Disclosure: former Hacker Schooler.
Great experience. If I were asked to name one criticism off the top of my head, though, it would be "gender gap." It was my first foray into tech, and I was a bit taken aback. Now I'm acclimated, but it's great to see they've got the resources to try and tackle the gap head on. The school always draws quite a few tech-experienced people who were in nontechnical (and not male-dominated) fields. This means they can bypass the whole four-years-of-classes-with-only-dudes problem that comes with expecting any shift from academia.